The Abbey

What started out as a cozy coffeehouse in 1991 has transformed into a happening West Hollywood gay bar. Lance Bass and Pamela Anderson come here for fun cocktails and conversation at night, but stop by for a low-key lunch to avoid the lively evening scene.

Huvane – who had been presented with the Piaget Award of Inspiration at the Grey Goose hosted amfAR Inspiration Gala at Milk Studios earlier that evening – arrived with the Sex and the City actresses just before 11 p.m.

"They didn't share any cosmos but were in good spirits, laughing with the others celebrating Huvane," an onlooker tells PEOPLE.

"Sarah and Kristin left together in the same car, which picked them up amid a crowd of excited fans and paparazzi," the source adds.

Already celebrating because of President Obama's announcement in support of same-sex marriage, the crowd at The Abbey Food and Bar in West Hollywood was in for an even bigger treat when Mariah Carey showed up out of the blue Wednesday night.

"There was no formal announcement that she arrived at the club, but she and her friend B. Scott held court at one of the main dance floor tables – so she was very visible," a partygoer tells PEOPLE of the singer, who recently renewed her vows in Paris. "She was very nice and gracious."

In honor of Carey's appearance, the deejay started playing her songs, which caused the ladies on the dance floor to "go crazy," the source says.

Even though the pop diva, who stuck around until 2 a.m. and took some shots of Beluga vodka, kindly posed for pictures with many people at the club, the insider explains, "A security guard had to stay by her booth to control her fans." – Dahvi Shira

Mom-to-beKristin Cavallari enjoyed a romantic lunch with fiancé Jay Cutler at Marble Lane Restaurant in New York. Both ordered the tomato soup, then one ordered the Caesar salad while the other opted for a lobster Cobb salad. According to a source, they seemed super happy, chatting the entire time. Says the source: "She was very smiley and looked radiant."

Meanwhile, days before her Big Apple visit for New York Fashion Week, Cavallari celebrated a friend's upcoming wedding with a bridal shower at West Hollywood gay bar The Abbey, which was decked out in piñatas for the occasion. – Kristin Boehm and Dahvi Shira

LeAnn Rimes was in good spirits during a night out at West Hollywood gay bar The Abbey. The country singer stepped out with a male and female friend, and the trio sat at a table on the dance floor, with Rimes drinking tequila. She also giggled as she checked out the go-go dancers. Says a source: "She definitely appeared to be having a great time." – Dahvi Shira

Gabourey Sidibe stopped by The Abbey in West Hollywood with a bunch of girlfriends. The ladies were sipping Belvedere martinis and having a good time. According to an onlooker, she was flooded with adoring gay fans all night, more than most celebrities at The Abbey, and she got a lot of compliments on her hair weave. – Dahvi Shira

They hang out on – and off – the dance floor! Dancing with the Stars partners Cheryl Burkeand Rob Kardashian hit up West Hollywood gay bar The Abbey, where the duo sipped Belvedere vodka drinks and seemed to be enjoying themselves, sharing laughs all night, according to an onlooker. – Dahvi Shira